The purpose of the proposed study is to examine the effects of alcohol consumption on (1) individuals' preventive and risk behaviors associated with contracting HIV, (2) the probability of HIV positive individuals being prescribed HIV medications and adherence to such medication, (3) health status, and (4) health care utilization and costs, including barriers to accessing health care and insurance coverage. These relationships will be analyzed using four databases: the HIV Cost and Services Utilization Study (HCSUS), Coping with HIV/AIDS in the Southeast (CHASE), the National Health Interview Surveys (NHIS) with linked mortality data, and the Medical Expenditure Panel Survey (MEPS). Alcohol impairs individuals' ability to think rationally, may increase risk behaviors such as unprotected sex or IV drug use, and may decrease prevention efforts such as testing for HIV. These relationships will be analyzed using NHIS, HCSUS, and CHASE. Alcohol alters the effectiveness of HIV medications in reducing the viral load. Physicians may avoid prescribing HIV medications to alcoholics for fear of the HIV virus developing drug resistance due to inadequate adherence to prescribed drug regimens. These relationships will be analyzed using HCSUS and CHASE. Alcohol weakens an individual's immune system and coping abilities, especially in HIV infected persons. The effect of alcohol on self-reported health and functioning, co-infections, and clinical markers such as CD4 count and viral load will be studied using HCSUS and CHASE. Heavy alcohol consumption reduces an individual's likelihood of being employed and having private insurance, and increases the likelihood of being on Medicaid or uninsured. Thus, alcoholic HIV infected persons are more likely to face problems in accessing adequate medical care. The relationship between alcohol, insurance coverage, health care utilization and costs will be studied using HCSUS, CHASE, MEPS and NHIS. The proposed analyses will greatly improve our knowledge of causal pathways due to the use of longitudinal data from multiple sources; provide estimates of cost associated with heavy alcohol consumption in HIV positive individuals; allow for national estimates for the U.S. population and for HIV positive adults; provide current estimates of the associations for the Deep South; and allow for an evaluation of changes in the relationships over time as our data span much of the time period since the beginning of the HIV epidemic.